LENS DRIVE DEVICE

摘要

The objective of the present invention is to provide a camera module capable of minimizing leakage flux by improving the yoke structure of a lens driving device for a camera. The lens driving device given in the present invention includes a lens holder which has a cylindrical shape to hold a lens assembly in which one or more lenses are accommodated and in which a driving coil surrounds the outer circumference of the cylindrical shape; a yoke unit in which a plurality of permanent magnets are fixed onto the inner wall of an outer yoke opposite to the driving coil and a plurality of lower yokes are placed in contact with the inner wall of the outer yoke under the permanent magnets, wherein the lower yokes are separable from the outer yoke and the lower part of the outer yoke is in contact with a base unit; and a pair of springs which includes an upper spring of which the inner circumference-side end part is placed at the optical axis-direction upper end of the lens holder and the outer circumference-side end part is placed on the yoke unit, and a lower spring of which the inner circumference-side end part is placed at the optical axis-direction lower end of the lens holder and the outer circumference-side end part is placed on the base unit and which supports the lens holder in the optical axis direction to be displaceable. By doing so, the size of the lens driving device and the size of a camera lens module including the same can be reduced. Also, a magnetic circuit with high magnetic efficiency can be built, resulting in reducing power consumption.